Resettable electric clock timer mechanism



June 11, 1968 J. F. MAR-CHAND 3,388,223

RESETTABLE ELECTRIC CLOCK TIMER MECHANISM Filed March 31, 1966 2Sheets-Sheet l INVENTOR. JOHN E MARCH/1ND A TTORNEY 1968 J. F. MARCHANDRESETTABLE ELECTRIC CLOCK TIMER MECHANISM June 11 2 Sheets-Sheet 3 FiledMarch 51, 1966 A M II.

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INVENTOR. JOHN E MARC/ AND ATTORNEY United States Patent Ofiice PatentedJune 11, 1968 3,388,223 RESETTABLE ELECTRIC CLGCK TIMER MECHANISM JohnF. Marchand, 445 E. 65th St, New York, NY. 10021 Filed Mar. 31, 1966,Ser. No. 540,476 Claims. ((11. 200-38) This invention relates to anelectric clock timer system which controls load circuits forpredetermined intervals,

and which resets itself after a certain operating time.

In the past electric clock timers have been used to control various loadcircuits at predetermined intervals, a good example being the intervaltimers on the ovens of electric ranges and the like. This timing effectis normally by contacts on a disc or other element of the timer which isrotated. The start up mechanism of such a timing system may be fairlyfast, for example, a manually operated pushbutton or dial which startsthe clock timer motor running and which acts over a fraction of a secondof operating time.

However, there are also situations in which the timing interval must beinitiated by a faster pulse, for example, one which may have a durationbest measured in the milliseconds. A problem then arises for some timingproblems by reason of the fact that the rotating member, such as thedisc of an electric timing mechanism, is one that turns slowly.

The present invention is one that permits a reliable, quick actuationwith relatively slower actuator systems, such as manual buttons, withoutany further element. On the other hand, the new operating principlewhich will be described below also provides for reliable operation withvery short action of the initiating pulse, but in such a case anadditional element in the form of a fast acting latch relay is necessaryin order to start and continue the movement of the timer motor for itspredetermined cycle.

The present invention functions by making use of a characteristic ofelectric clock timers which normally is considered an unavoidable evil,namely the fact that any rotating mechanism builds up a rotary momentumand so tends to overshoot when the driving torque ceases, unlesselaborate or expensive damping mechanisms are used. This inherentcharacteristic, which has previously been considered a drawback, is putto use in the present invention to provide a reliable resettingarrangement. In some cases it is even desirable to increase this naturalovershoot tendency a little by adding predetermined weight to the movingparts, thus producing an additional flywheel effect of just the extentneeded. Thus by making use of a motor timer characteristic which wasonly a drawback the present invention achieves an important new effectthat works reliably and permits a simpler and cheaper type of intervaltimer construction. In fact, expensively damped constructions are noteven useful in the present invention. Instead, satisfactory reliabilityis obtained by a new way of utilizing the rotor momentum of a shadedpole motor and this improvement permits economies by simpleconstructions. The present invention is thus an electric clock systemthat includes a timer of particular design in combination withparticular start up systems that are appropriately fast or very fastdepending on their role in the operation of the timer, and it is thewhole of the combination that constitutes the invention rather than anyone element thereof.

The present invention is a simplified timing mechanism that can be usedfor a useful series of timing intervals suitable to its capabilities,and one that can be used with a wide range of electrical loads eitherdirectly or else with suitable ordinary relays where the power demandsof the control load are beyond the current carrying capacity of thetimer mechanism itself.

In my prior application, Ser. No. 338,235, filed I an. 16, 1964, Idescribed and claimed fixed delay commercial squelch circuits fortelevision and radio receivers which shut off sound during the time whena commercial announcement is being broadcast. This is one field in whichthe new timing mechanism of the present invention may be used and, infact, in the specific description in conjunction with some of thedrawings such a use will be described as a typical illustration.However, the invention is not limited to this use. Also it should bepointed out that in my prior application modifications of electrictimers were described. However, none of these involved a momentumovershoot effect for resettability. The initiation of timing was by amanually operated pushbutton or by a quick remote control pulse. Where avery simple fast initiation by a manual pushbutton is wanted, thepresent invention eliminates the need of a latching relay to get quickenough action, and where this type of actuation is practical theelimination of a hitherto needed relay makes this modification anattractive one.

It is also possible in a more elaborate modification of the presentinvention to operate with timing intervals that vary widely, for exampletiming of a few minutes, as is illustrated for commercial squelching,photographic timing and the like, and longer intervals, such as forexample intervals of some hours, by means of the same timer. The longintervals require a latching relay, but it is an advantage that theovershoot principle of the present invention may be used for the shortertime intervals coupled with what might be considered a mechanicalovershoot for the longer timing intervals by the addition of a suitabletype of switch. The possibility of handling several different timingproblems permits a flexibility and versatility which is a practicaladvantage of the present invention for certain uses. This additionalflexibility is obtained without compromising the reliability andsimplicity which are basic features of the present invention.

The invention will be described in greater detail in conjunction withthe drawings in which:

FIGURE 1 is an isometric illustration of one mod fication;

FIG. 2 is a detailed view on a larger scale of a different and preferredmodification;

FIG. 3 is a diagrammatic illustration of the basic principles of thepresent invention, and

FIG. 4 is an isometric view of a modified mechanism permitting very longas well as very short intervals from the same timer.

FIG. 3 is a diagrammatic illustration of the principles under which thepresent invention operates. For this purpose a conductive path, whichmay be on a switch disc, is shown drawn out in a straight line at 32. Acontact 33 moves over the path when the latter is turned, as on a timerdriven disc. 34 shows the distance through which the timer mechanismmoves after power has been shut off from the timer motor. That is tosay, this is the momentum overshoot for the particlar mechanism. Twodifferent kinds of interrupting, insulating segments 35 and 36 areshown, the former being much narrower than the overshoot 34 and beinguseful with modifications employing a locking relay or similarmechanism. The broader segment 36 can be used where a locking relay isto be eliminated. In FIG. 3 the relative size of the overshoot distanceand insulating segments is very greatly exaggerated for clarity. Inactual construction the insulating segment 35 can be of the width of ahuman hair or still narrow, with of course the other dimensions ofovershoot and wider segment 36 in proportion.

If We assume that the timer was running with the path 32 moving underthe switch blade 33 and if we assume that there is a locking relay inseries between the blade 33 and the motor circuit, as will beillustrated and described in connection with FIG. 4, when the bladereaches the extremely narrow insulating segment 35, the locking relaybecomes unlocked or unlatched, but the momentum carries the switch bladepast the insulating segment. However, the timer does not continue tooperate because the latching relay is in series in the motor circuit andit has become unlatched. Now when a starting pulse, even a very shortone, initiates another cycle, the relay is locked, and as the blade 33has moved to a further part of conducting segment, the timer will startup again. In other words, the overshoot has put the blade 33 in aposition where the timer is reset and ready to be started on command.

Where a slower actuation, such as a manual pushbutton, is present,bypassing the blade 33 while the button is depressed, the widerinsulating segment 36 is employed. It will be noted that this segment isa little wider than the distance 34 of overshoot. Thus, when the blade33 strikes the insulating segment and the motor power is shut off, thetimer mechanism coasts or overshoots a distance somewhat less than thewidth of the segment 36. Now when the pushbutton is actuated to startanother timing cycle and bypasses the insulation, the motor startsturning immediately, and before the button can be released the blade 33has moved off the far edge of the segment 36 onto conducting path oncemore and the motor continues to turn through a full revolution. In bothcases the overshoot has resulted in resetting the timing mechanism, sothat when a new actuation is started the timing mechanism will gothrough a whole cycle.

FIG. 1 shows anoverall isometric of a typical electric clock timer withdiscs in which timing is effected on the disc periphery. This makesillustration of a typical simple circuit easier, but the construction isless compact for the same degree of versatility than that of FIG. 2 andso, for many purposes, is not preferred.

The electric timer motor, of the standard self-starting synchronoustype, is shown as connected to a 110 volt AC line with a grounded wireand a hot wire 2 using a polarized plug 3. The timer motor rotates agrounded shaft 31 on which are fastened two conducting discs 4 and 5.The first disc controls the motor circuit and is provided with a narrowinsulating segment 9. As has been described above, this may be of theorder of width of segment 36 in FIG. 3 but in the drawing is shownexaggerated for clarity. A leaf contact 6 rides on the disc 4 and isconnected to the motor, completing its circuit. In other words, when theleaf 6 is in contact with the conducting portions of the periphery ofthe disc 4, the motor will turn.

A pushbutton switch 7 is shown which momentarily bypasses the switch 6and when depressed starts the motor. As has been described above, theinsulating segment 9 is so narrow that the momentum of the timer when itis shut off moves the disc 4 for a distance such that while it stopswith the blade 6 still in contact with the insulating segment, it isnear enough to the edge so that when the pushbutton 7 is depressed andthe timer motor starts turning the disc 4 will move to a point where theblade 6 is in contact with the conducting portion of the disc. It shouldbe noted that we are dealing with finite times, the timer not stoppinginstantaneously when power is shut off as the blade 6 strikes thesegment 9; and also the actuation of the pushbutton 7 is likewise notinstantaneous and may take from a substantial fraction of a second to asecond or more, depending on how fast the button is manually actuated.The simple form of the present invention which has been described inconnection with FIGS. 1 and 2 is not suitable for operation whereinitiation time is extremely short. For this purpose a locking relay orits electronic equivalent is still needed, and the cornbination of thepresent invention with such an element will be described below inconjunction with FIG. 1, which also illustrates the combination of shortintervals and very long intervals on ditferent discs.

When the pushbutton 7 has been momentarily depressed the timer starts,the blade 6 reaches the conducting portion of the disc 4 and the timercontinues throughout its cycle until the blade 6 again strikes thesegment 9. A second disc 5 cooperates with a second blade 3 whichgrounds the load 28 and starts whatever operation the load circuitcontrols. As the present invention is not limited in its broader aspectsto any particular type of load, such as a commercial squelch device, itis shown diagrammatically. When the motor starts the disc 5 moves untilthe blade 8 has left the wider insulating segment 10. This segment isnot quite as greatly exaggerated as is segment 9 and provides a maximumreliability so that when the timer has turned through a full cycle theload is disconnected by the insulating segment 10 when the motor stops.The greater width of the segment 10 assures that the load is cut offreliably at the end of the cycle.

Unless polarizing sockets are used with a polarizing plug 3 themodification of FIG. 1 is not suitable for muting the audio systems oftelevision sets and radios because if there is not polarization of theincoming wires, the switch blade 8 could put the hot lead of the 110volt circuit on the voice coil of a loudspeaker or other portions of theaudio circuit, With undesirable, and in some cases disastrous, results.Also, for many purposes it is desirable to isolate completely the audiosystem of a television or radio receiver from the 110 volt line in ordernot to pick up stray signals. In such a case, even with a polarizingsocket and a polarizing plug 3 the modification is not desirable.However, for other operations, such as for example a coffee percolatoror toaster, it is a matter of complete indifference to the applicancewhich wires connect it to the ungrounded side of the AC line, and forsuch uses the modification shown in FIG. 1 is suitable, of course usinga relay, but not a locking relay, in the load 28 if the powerconsumption is such as to require it. If there is no provision forpolarization of the power line coming in, there is the possibility thatthe shaft 31 will be connected to the hot side of the AC line, and insuch cases the timer mechanism should be reliably enclosed,if necessaryproviding for power cord interlock if the timer is open, to eliminateshock hazard. These are conventional precautions with electricappliances and are, therefore, not illustrated.

FIG. 2 represents a construction which, for many purposes, is preferableto the simple one of FIG. 1. Only the switch disc is shown with switchblades, the motor shaft 31 of course being turned in the same way as inFIG. 1. The disc, which is shown as insulating, is provided with acontinuous conductive ring 14 which is connected to one end of the loadcircuit through the blade switch 13. In the drawing this is illustratedas a muting loud speaker 26 for squelching of commercial circuits, thevoice coil 27 of the speaker being shorted during the squelchingintervals, as will be described below. The disc carries two additionalconducting paths 23 and 24 on which ride blade switches 15 and 16. Bothconducting paths are connected to the path 14 through the connector 25.The two blades 15 and 16 are connected to two contacts of a single poledouble throw switch 17, the movable contact 18 of which is connected tothe other end of the voice coil 27. It will be noted that the connectingpath 24 extends for almost a complete circle with an insulating gap 20which corresponds to the insulating segment 10 in FIG. 1. The conductingpath 23, however, extends only half way around the disc, the remainderof the distance being an insulating path which is indicated at 21 andwhich in effect performs for this path the same functions as does theinsulating gap 28 for the path 24.

On the periphery of the disc there is a wide conducting circle 22 whichextends all the way around the disc except for a very narrow insulatingsegment 19, which is of the same dimensions and performs the samefunction as does the corresponding segment 9 in FIG. 1. It, too, isexaggerated for clarity. Two blades 11 and 12 ride on the path 22, andof course the insulating segment 19 when they reach it, and areconnected to the timer motor and to ground respectively, as is indicatedschematically. A starting pushbutton, (not shown), is provided as inFIG. 1.

Also, the single-pole double-throw switch 17 is adjusted to choose thetiming intervals desired. Let use assume that it connects the movingcontact with blade 15. Also let us assume that the timer is in the resetposition, i.e., the motor shut off but ready to start, which isillustrated on the drawing. Now, the initiating pushbutton is depressed,the timer motor starts, the disc moves slightly so that the blades 11and 12 ride on thewide conducting path 22, and the timer continuesbecause there is a completion of the circuit to the motor. As the path24 extends all the way around the disc except for the insulating segment20, the loudspeaker will be muted for a full turn of the timer disc; inother words, the timing will be the same as shown in FIG. 1, and if thetimer shaft 31 turns at 1 r.p.m., this will squelch the loudspeaker 26for one minute.

If a shorter interval is desired, the switch 17 is thrown connecting theloudspeaker coil to switch blade 16 and now when another cycle isinitiated it will only last for half a minute, as the circularconducting path 23 extends for only half way around the disc. The timercontinues to turn through its full cycle but as the path traversed bythe blade 16 is over insulation, the loudspeaker remains unmuted untilthe timer has gone through its cycle and another squelch cycle isinitiated by voluntary actuation of the initiating button.

It will be noted that there is an extremely simple switch construction,requiring only a' single disc, the conducting portions of which canreadily be applied by printed circuit techniques, using, of course,conductors sufficiently thick so that they will not be worn through. Theblades 11, 12, 13, 15 and 16 are shown perfectly tangential. It isnecessary that they be somewhere near tangential to avoid unnecessarywear on the conductive paths. However, they do not have to be perfectlytangential, as if they make a small angle no significant wear results.

FIG. 2 shows a system in which the motor actuation is completelyisolate-d from the switching of the load circuit for the intervalschosen. This is quite suitable for squelching of the audio in atelevision and radio receiver during commercials, and so this particulartype of load circuit is illustrated as being typical of one for whichthe complete isolation of motor control and load circuits is suitable orrequired. Obviously, of course, any other load circuit may be used.

When a single disc of small size is used as in FIG. 2, it is generallyundersirable to provide for more than twotiming intervals on the samedisc, through of course with sufiiciently narrow blades more can beaccommodated, with a selecting switch having more than two poles. Withsmall discs it is generally preferable to connect a second disc, or morein an extreme case, where there are a larger number of timing intervalsto be selected. The operation of course proceeds in exactly the samemanner, and a conductive path 14 must of course be present on the seconddisc. It is also practical to use both sides of the disc, in which casethe path 14 need not be repeated but the paths 23 and 24 can beconnected through the disc to the conducting paths on the other side. Itis also possible to have the contact path 22 appear on bothv sides ofthe disc and have one blade 11 on one side and the other blade 12 on theother side. A path of narrower width is thus made possible. It is notnecessary to duplicate the insulating segment 19, as of course thecircuit is broken if either blade 11 or blade 12 strikes an insulatingsegment.

For certain purposes it is desired to interrupt connection to a load forthe particular timing interval. This is simply done by interchanging theconductive andnonconductive portions of the paths 23 and 24 with gaps 20and 21 and, of course, connecting the path 14 to the gaps. In such acase when the timer is at rest the load is connected, but it isdisconnected as soon as the timer is started and the blades 15 or 16have reached an insulating portion for the time interval chosen.Thereafter the connection is not remade until another cycle isinitiated.

FIG. 2 shows a mechanism which is quite versatile, as the load iscompletely isolated from the timer motor. However, for certain purposes,such as electrical appliances, this isolation is not needed. In such acase a simpler load circuit arrangement with a common ground, as isillustrated in FIG. 1, can be employed. Of course in such a case theblade 13 and paths 14, 22 and 23 are all connected together. The load,as in FIG. 1 is permanently connected to one side of the AC line and theother side is grounded. In this case, of course, a single narrowconnecting path 22 can be used, as it is not necessary to have twoseparate blade switches 11 and 12, which are shown in FIG. 2, to permitthe stopping the motor.

FIG. 4 illustrates a combination of switching for short intervals andlong intervals. As in FIG. 2, where the disc 5 is used for shorter timeintervals, the conducting paths and switches bear the same referencenumerals except that only one switch 11 is used for the motor circuit.Disc 5 turns on a hollow shaft 37, whereas the solid shaft 39 turns adisc 38. Both shafts are grounded and are connected to the conductingpaths of disc 5 and a conducting path 40 of disc 38-. Blade 41 movesover the latter, and the insulating segment 42 can be quite broad.Through conventional gearing, disc 38 may be made to turn much moreslowly than disc 5. For example, if the latter makes one revolution intwo minutes, the former may make one revolution in an hour or two hours.

The load 28 and one side of the motor is connected to the hot wire 2 ofthe AC line, as in FIG. 1. One pole of a double-pole, double-throwswitch 43 can switch the load either onto the blade switch 41 for slowtiming or to one or other of the switches 15 and 16 of the fast timer,the latter two being selected as described in FIG. 2 by the single-pole,double-throw switch 17, the movable pole 18 of which is connected to oneof the contacts of the double-pole switch 43. A locking relay 44 isprovided in the motor circuit and is connected to movable contact on thedouble-pole switch 43. When this switch is in the lower position theconnection .is through the blade 11 to the grounded path 13 on disc 5.In the upper position the connection is to a normally closed microswitch45 which is actuated by a smallbump 46 in the disc 38. This disc isprovided with a small amount of play so that when the disc 38 lifts theswitch 45 by the bump 46, thus momentarily opening the circuit to thelocking relay 44 and unlocking it, the play permits the switch 45 toslide down the bump, thus producing an operation analogous to a toggleswitch. The locking relay has been unlocked, how ever, and as it is inseries with the switch 45 the motor does not continue to turn untilanother sequence of operation is initiated by a starting button orstarting pulse. When such a pulse is received, and it can be very shortcomparted to the time it takes to operate a manual pushbutton, the relay44 locks and stays looked through the switch 45 until a full revolutionof the disc 38 has taken place. Since a locking relay is necessary foractuation from the slow turning disc 38, the gap 19 on disc 5 is verynarrow, corresponding in relative dimensions to a narrow segment 35 inFIG. 3. If the switch 43 is in its lower position the overshoot on thedisc 5 when it has completed a revolution causes the blade 11 to passover the narrow insulating segment 19, and now when the latching relayis once more actuated the motor will continue to turn, while the blade11 runs along the conducting path 22 on disc 5.

FIG. 4 illustrates at the same time the provision for long and shortintervals and the use of a locking relay with a narrow insulatingsegment. A narrow segment and locking relay may be incorporated in theconstruction of FIGS. 1 and 2 where this is desirable, as for examplewith a very fast, remote control instead of a manual pushbutton.

It will be seen that the present invention is a versatile one that canbe used with or without a latching relay, depending on the conditionsrequired. As pointed out above, a latching relay is required where thereis a very slow interval or where the actuation is much faster than bymanual pushbutton, as for example in a device in which a remote controlwith a short electrical pulse is used to start a timing cycle. In eachcase the same principle of timer overshoot is used. The slight play inthe disc 38 described in FIG. 4 together with the toggle eifect of thebump 46 and the switch 45 in effect produce an overshoot. Even thoughthe disc turns slowly, this overshoot is magnified by the fact thatthere is enough play so that once the switch 45 has passed over thehighest point of the bump 46, it can snap down again on the other sideto its normally closed position.

I claim:

1. In a synchronous electric clock timer of the selfstarting varietyprovided with slow turning switching elements and switching conductingpaths thereon, said clock timer having a finite but definite overshootwhen power to the timer motor is shut oif, the improvement whichcomprises,

(a) at least one rotatable switching element connected to be rotated bythe timer,

(b) a motor controlling conductive path on at least one rotatableswitching element, said path having an insulating segment of sizerelative to the overshoot of the motor, at least one blade switchcontacting said path and connected to motor switching means for theclock motor, whereby when the rotating element causes the blade switchto contact the insulating segment the motor stops after a predetermineddistance of overshoot,

(c) means for momentarily starting the timer motor for a sufficientperiod of time so that the blade switch comes in contact with aconducting portion of the path whereby the motor continues to turn,

(d) switching elements rotated by the timer having at least oneconducting path and blade switches cooperating therewith to changeelectrical connections of a load circuit, said conducting paths beinginterrupted with insulating segments longer than the distance ofovershoot of the timer motor whereby on momentarily starting the timingmotor a load switching cycle is initiated and takes place through atleast one predetermined interval determined by the relative lengths ofthe conducting path and non-conductive segment, and on completion of thetiming cycle the timer is reset to initiate a new cycle when themomentary motor actuating means is energized.

2. A timer mechanism according to claim 1 in which the rotating elementcontains a conductive path and at least one blade switch in circuit withthe motor, and the insulating segment in the conducting path is slightlylonger than the distance of timer motor overshoot, and the momentarymeans for starting the timer motor have an actuation time constantlonger than the time required to move the rotating element through theremaining portion of the insulating segment, whereby on momentarystarting of the timer motor the blade switch again contacts a conductiveportion of the path and thus maintains the motor in operation foranother cycle.

3. A timer mechanism according to claim 2 in which two blade switchescontact the conductive path for maintaining motor operation and meansfor isolating the load circuit from the motor circuit during operation.

4. A timer mechanism according to claim 2 in which the rotating elementis provided with a plurality of conducting paths of different lengthswith blade switches in each pathand means for selectively connecting theload circuit to any one of said paths.

5. A timer mechanism according to claim 1 in which the rotating elementis provided with a plurality of conducting paths of different lengthswith blade switches in each path and means for selectively connectingthe load circuit to any one of said paths.

6. A timer mechanism according to claim 1 in which the motor circuit isprovided with a latching relay, the latching elements of said relayconnected through the conducting path for motor control and theinsulating segment is shorter in width than the overshoot of the timermotor, whereby when the segment is encountered, the locking relay isunlocked but the overshoot carries the switch blade past the insulatingsegment and the momentary motor actuating mechanism momentarily locksthe locking elements of 'the locking relay, which remain locked throughthe conducting path until the insulating segment is again reached.

7. A timer mechanism according to claim 6 in which there are a pluralityof conducting paths of different lengths with blade switch in each pathand selecting means for connecting the switches of any one path to theload circuit. g

8. A timer mechanism according to claim 7 in which the motor circuit iscompletely isolated from the load switching circuits.

9. A timer mechanism according to claim 5 comprising a plurality ofrotating elements, means for rotating the elements at dilferent rates,at least one of which is very slow, and snap acting switching means onsaid slow rotating element for unlatching the locking relay at the endof said long time interval.

10. A timer mechanism according to claim 9 in which another of the discsturns rapidly and has a motor control path and cooperating switch withan insulating segment shorter than motor overshoot on the disc inquestion.

References C'ited UNITED STATES PATENTS 1,244,408 10/1917 Bacon 200-36 X1,679,781 8/1927 Peyton et a1. 200-36 BERNARD R. GILHEANY, PrimaryExaminer.

F. E. BELL, Assistant Examiner.

1. IN A SYNCHRONOUS ELECTRIC CLOCK TIMER OF THE SELFSTARTING VARIETYPROVIDED WITH SLOW TURNING SWITCHING ELEMENTS AND SWITCHING CONDUCTINGPATHS THEREON, SAID CLOCK TIMER HAVING A FINITE BUT DEFINITE OVERSHOOTWHEN POWER TO THE TIMER MOTOR IS SHUT OFF, THE IMPROVEMENT WHICHCOMPRISES, (A) AT LEAST ONE ROTATABLE SWITCHING ELEMENT CONNECTED TO BEROTATED BY THE TIMER, (B) A MOTOR CONTROLLING CONDUCTIVE PATH ON ATLEAST ONE ROTATABLE SWITCHING ELEMENT, SAID PATH HAVING AN INSULATINGSEGMENT OF SIZE RELATIVE TO THE OVERSHOOT OF THE MOTOR, AT LEAST ONEBLADE SWITCH CONTACTING SAID PATH AND CONNECTED TO MOTOR SWITCHING MEANSFOR THE CLOCK MOTOR, WHEREBY WHEN THE ROTATING ELEMENT CAUSES THE BLADESWITCH TO CONTACT THE INSULATING SEGMENT THE MOTOR STOPS AFTER APREDETERMINED DISTANCE OF OVERSHOOT, (C) MEANS FOR MOMENTARILY STARTINGTHE TIMER MOTOR FOR A SUFFICIENT PERIOD OF TIME SO THAT THE BLADE SWITCHCOMES IN CONTACT WITH A CONDUCTING PORTION OF THE PATH WHEREBY THE MOTORCONTINUES TO TURN, (D) SWITCHING ELEMENTS ROTATED BY THE TIMER HAVING ATLEAST ONE CONDUCTING PATH AND BLADE SWITCHES COOPERATING THEREWITH TOCHANGE ELECTRICAL CONNECTIONS OF A LOAD CIRCUIT, SAID CONDUCTING PATHSBEING INTERRUPTED WITH INSULATING SEGMENTS LONGER THAN THE DISTANCE OFOVERSHOOT OF THE TIMER MOTOR WHEREBY ON MOMENTARILY STARTING THE TIMINGMOTOR A LOAD SWITCHING CYCLE IS INITIATED AND TAKES PLACE THROUGH ATLEAST ONE PREDETERMINED INTERVAL DETERMINED BY THE RELATIVE LENGTHS OFTHE CONDUCTING PATH AND NON-CONDUCTIVE SEGMENT, AND ON COMPLETION OF THETIMING CYCLE THE TIMER IS RESET TO INITIATE A NEW CYCLE WHEN THEMOMENTARY MOTOR ACTUATING MEANS IS ENERGIZED.